What's wrong with my triangle?

I have pretty long legs and I get the triangle position a lot (head and arm in legs, with ankles crossed, legs not yet triangled) and I can never finish the triangle choke. I learned it with keeping the head down, pull the arm across, get a slight angle on his neck then triangle the legs and finish. However, my opponents always end up able to pull their heads out and pass my guard during the transition where I'm getting angle on their neck and opening my legs, right before triangling the legs. They aren't going away from their arm, giving me the omoplata, either. They just pull the head straight out then leave the arm inside my legs and go for the pass.

I've asked my instructor and he says to just keep practicing until I get the feel for it, but it's been a while and this happens all the time. Should I be squeezing harder with my legs to keep their head trapped? Should I be pulling the head down or holding on to the collar throughout the move? Or do I just need to be faster at getting angle and triangling my legs so they don't have enough time to pull out?

it sounds to me like you don't really have a triangle at the point they're escaping. if your ankles are crossed over the head but your calf isn't clamped behind the neck, you're not there yet, & you have to adjust before trying to finish. pull the head down, then use your opposite hand to grab your own ankle and pull it down to the point where you can lock the triangle with the opposite leg. also, be sure to pull the trapped arm all the way across, cutting off the wiggle room between his shoulder & throat.

long legs are a huge triangle advantage; I'm 6'2" and they probably account for 60% of my subs, maybe 90% from the guard.

Why have there been two posts and no one has told him he needs to squeeze his knees together?

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Why have there been two posts and no one has told him he needs to squeeze his knees together?

If you squeeze your knees together while attempting to pull your heels toward your own butt (exerting a contracting force with your lower legs), he will not be able to pull his head out. Also make sure to curl your foot toward your own shin in order to flex your calf muscle as this increases the tightness of the triangle.

You stated 'get a slight angle on the neck'. The MINIMUM angle you should strive to attain should be your body alignment at a 45 degree angle in relation to his shoulder opposite the trapped arm. Basically, the closer your angle is to being perpendicular to his body's alignment, the stronger the triangle.

I haven't grappled for a while (boo hoo) but I used to get wrecked by one guy when I would try to pass while he was trying to triangle me. He would hook a leg (a good idea anyway) to prevent me from moving for a second and then transition to an armbar with both legs on my head. It was almost exactly like this http://www.bjj.org/techniques/jen/tech17/

Eventually someone will catch on, but I'd say it's worth a try.

Edit: I just noticed that the guy in white in the picture crosses his head side foot on top of his body side foot, which I was told is a bad idea and should be done the other way around. I've never done it the way shown in the picture in terms of foot/leg placement, so I couldn't say, but I thought it should be known.

Long legs are a big advantage for many attacks from the guard. Personally, I have short legs, which makes triangles more difficult. If I understand you correctly, the difficulty lies in the fact that they somehow break your ankles open before they are triangled? In order to avoid this I put a lof of effort into breaking their posture; usually by pulling their sleeve while simultaniously pulling my foot into place with my other hand. This might be what you are doing wrong.

However, your instructor is right: most likely you have the theory down and just need practice. You might, for example, be applying the triangle in spots where it is not a good response. I am also by no means a triangle expert (actually my triangle sucks), but hopefully you got something out of my response.

I pointed at him [the panhandler], bringing my rear hand up in a subtle approximation of the double Wu Sau guard that is the default hand position in Wing Chun Kung Fu.

Thanks for the responses so far. In transitioning from the ankles crossed to the legs fully triangled, I generally have to open my legs slightly to reposition. It is at this moment, when I'm opening my legs and angling, that they pull the head out.

I know long legs are better for guard, especially triangles, and I want to get better at them. My armbars, omoplatas and sweeps are already pretty effective (against other white belts) and this is the one submission I consistantly fail at.